Artificial foot



Filod May 5, 1924 if 'Y 'fr f *i f S is wedged.

Patented Aug. 12, 1924.

JAMIS F. ROWLEY, 013|* CHICAGO, ILLINOIS.

ARTIFICIAL FOOT.

Application filed May 5, 1924. Serial No. 711,170.

To all whom it may concern.'

Be it known that I, JAMEs F. RowLEY, a citizen of the United States ofAmerica, and a resident of `lChicago, county of Cook, and State ofIllinois, have invented new and useful improvement in Artificial Feet,of which the following is a specification.

The main objects of this invention are to provide an improved artificialfoot; to provide an improved form and arrangement of cushioning meansfor yieldingly resisting` the relative movements of the articulatedparts to as nearly as possible similate the action of the natural footin absorbing the shocks incident to the tread of the footv and theshifting ofthe weight from one part of the foot to the other during theact of walking or running; to provide a pair of opposing spring cushionsnormally holding the foot in a natural unleXed position; and to providea buffer cushion which only acts when the flexure of the foot exceedsthe predetermined limit.

An illustrative embodiment of this invention is shown by theaccompanying drawings, in which.:

Figure 1 is a sectional elevation of the improved form of a foot showingthe position of opposing springs and the bui'ler cushion.

In the specific embodiment herein shown, the foot comprises a leg memberor shin section 1 and the foot core 2 articulated thereon by means of aball-bearing hinge 8 comprising bolts 4 and 5 connected together by apivot 6 which is `iournaled in ball-bearings.

The shin section 1 is hollowed out so as to provide a tapered socket 7in which a plug` The plug 8 provides a selflocking support for bolt 4.An angle faced member 9 extends across the bottom of the shin sectionand coaots with the plug 8 for supporting the bolt 4. The lower face ofthe base 9,y slopes upwardly/ at substantially the same angle towardsthe toe and the heel of the foot. The wooden foot core 2 is embedded ina foot form or body 10 made of sponge rubber and conforming to thegeneral shape of the human foot. The upper face of this foot core 2 issubstantially horizontal between the hinge and the heel and is chamferedforward of the hinge to form a base for the rubber cushion 12. The lowerface of the foot core 2 adjacent to the front is curved at 13 so as toprovide a kind of recess or pocket which tends to resist the spreadingor creeping of the sponge rubber along the core when the pressure isupon the ball of the foot. The improved cushioning means comprises twospring rubber blocks 14 and 15 andthe spring rubber buffer 12. Thespring rubber blocks 14 and 15 'are interposed between the oppositefaces of the core 2 and the shin baseV 9 at opposite sides of the hinge.These springs 14 and 15 are formed of firm, live rubber so that whilethey are capable of yielding` they otter considerable resistance land assoon as the vpressure is relieved .they resume their original form andvolume. The spring blocks 14 and 15 are preferably of cylindrical formand the heel block14 extendsI through a hole near the rear end of thefoot core 2 and is slightly inclined forwardly at an angle to thevertical. The upper end of this cylindrical block 14 is seated in arecess 16 formed in the under face of the base l plate part 9. The lowerend of the spring block 14 is embedded in sponge rubber which forms theheel portion of the foot form 10. These springs 14 and 15 are equal andopposite in action, normallyrestoring, the foot to the unflexedpositionand so disposed that the tension required for `fiexure is directlyproportional to the angle of flex-` ure and is the same for both heeland toe. The buffer disc 12 is seated in a beveled base formed in thefoot core 2 where it is secured against dislodgement. The forward or toespring block 15 is placed in the opposing relation to the bock 14 by`being seated in recesses in the shin section 1 and the foot section 2 atsubstantially equivalent distances and angles. At the normal footposition there is provided a clearance between the buffer cushion 12 andthe shin section 1, the upper surface of the buffer cushion being formedto coact with the shin section when the toe has been bent upward to apredetermined angular limit.

The two pieces of spring rubber 14 and 15 located between thearticulated parts of the foot at opposite sides of their connectionserve to yieldingly resist the relative shift-ing of said parts and givea smooth and even resilience which occurs in the normal process ofwalking. This invention provides a spring buffer which comes into playwhen any unusual leXure is required and the spring buffer provides forthe toe fiexure a shock absorber somewhat equivalent to that provided bythe spring block 14 which is carried through the core section andenibedded in the live rubber of the heel. The spring buli'er inoperation has lateral eXpansion when lLinder axial compression. Thepresence of the bufler in the toe section makes it possible to provide amore sensitive restoring action in the adjustmentof the tension of thesprings 14 and 15. The action of the three springs as placed, gives amuch more natural action of the foot than has heretofore been developed.

Although but one specific embodiment of this invention has been hereinshown and described it will be understood that numerous details of theconstruction shown may be altered or omitted without departing from thespirit of this invention as defined by the following claims.

I claim:

1. An artilicial foot comprising a leg member, a foot core liingedlymounted beloW said leg member, opposed spring rubber cushions comprisinga heel cushion and a toe cushion, said heel cushion extending into arecess in said legv member and extending through said foot core, saidtoe cushion extending" into recesses bearing directly between said legmember, and said foot core and a buifer'cushion secured to said footcore.

n 2. An artificial foot, comprising a shin y section, a foot corehingedly mounted thereon, a foot form supported on and surroundingsaidfoot core, a heel block of spring rubber extending through the rear endof said foot core and having the upper end bearing against said shinsection and the `lower end embedded in the heel portion of said footform, a toe block of spring rubber seated in recesses and interposedbetween said shin section and foot core forwardly of the hingedconnection, and a buifer block secured to the upper surface of said footcore.

3. An artificial foot comprising a shin section, a foot core hingedlymounted thereon, a foot form supported on and surrounding said footcore, and a spring rubber buffer mounted on the upper surface of saidfoot core and spaced away from said shin section, and a pair of opposingspring rubber members seated in recesses forward and rearward of thehinge.

t. An artificial foot, comprising a shin sect-ion, a foot core hingedlymounted there- (on, a foot form supported on and surrounding said footcore, a heel block of spring rubber extending through the rear end ofsaid foot core and having the upper end bearing against said shinsection and the lower end embedded in the heel portion of said footform, a toe block of spring rubber seated in recesses on the toe side ofthe hinged connection in said shin section and foot core, and a springrubber buffer fastened to the foot core forwardly of the hingedconnection, said core being chamfered to receive said buil'er to secureit against dislodgement but permitting the lateral expansion of saidbutler when coinpressed axially between said core and said shin section.

Signed at Chicago this 30th day of April, 1924.

JAMES F. ROVVLEY.

